1. Field of the Invention
The present invention relates to containers for dispensing substances including edible substances, and more particularly, to improved containers including one-way valves and collapsible and/or squeeze tubes that maintain the product in an airless and/or sterile condition during repeated dispensing.
2. Background of the Related Art
Flexible tubes and the like are used to store a variety of substances including edible foods and beverages having a broad range of viscosities. Generally, the flexible tubes have a cover which is removed to expose a simple release aperture through which the stored substance is dispensed. As a result, low pressures are required to dispense the substance thereby causing unwanted oozing and build-up, which ultimately leads to inhibited flow and clogging at the release aperture. Moreover, when the traditional tube is opened during operation, the contents are continually exposed to the ambient environment, thus exposing the contents to bacteria, germs and/or other impurities during and/or after the product is dispensed. Furthermore, unwanted air is often drawn into the tube which facilitates the spreading of the bacteria, germs and/or other impurities with each subsequent use, and also negatively impacts the flow characteristics of the substance during dispensing, such that the substance is dispensed unevenly, contains air bubbles or continues to ooze out unwantedly. Despite techniques for sterilizing the stored contents prior to opening, this constant exposure to the environment has the negative effect of degrading the stored substance, thereby limiting the shelf-life and range of products suitable for dispensing via tubes. As a result, such products must include preservatives in order to prevent the product remaining in the container from spoiling or otherwise degrading between usages. One of the drawbacks associated with preservatives is that they can cause an allergic or an otherwise undesirable reaction or effect on the user and/or product. In addition, the preservatives do not prevent the bulk product stored within the open container from collecting, and in some cases, facilitating the spread of contamination.
In view of the above, several containers have been provided with closure devices such as one-way valves. One drawback associated with prior art dispensers including one-way valves is that the valves are frequently designed to work with mechanical pumps or like actuators that are capable of creating relatively high valve opening pressures. Exemplary dispensers of this type are illustrated in U.S. Pat. Nos. RE 37,047, 6,032,101, 5,944,702, and 5,746,728 and U.S. Publication Nos. US2002/0074362 A1, US2002/0017294 A1. Squeeze tube-type dispensers, on the other hand, are not capable of creating the necessary valve opening pressures, and therefore such prior art valves do not work effectively with squeeze tubes.
Accordingly, it is an object of the present invention to overcome one or more of the above-described drawbacks and/or disadvantages of the prior art.